Tiao Game Rules

Tiao (跳, "jump") is a two-player strategy board game played on a 19x19 grid. Players compete to capture enemy pieces by jumping over them, similar to checkers but on a Go-sized board with unique placement constraints.

Setup

• The board starts empty.
• Two players: White and Black.
• White always moves first.

The Board

A 19x19 grid of intersections. Small dots mark the nine star points for orientation:

  0 1 2 3 4 5 6 7 8 9 ...
0 . . . . . . . . . . ...
1 . . . . . . . . . . ...
2 . . . . . . . . . . ...
3 . . . * . . . * . . ...
4 . . . . . . . . . . ...
5 . . . . . . . . . . ...
...

Player Actions

On your turn you do exactly one of the following:

1. Place a Piece

Put one of your pieces on any empty intersection, subject to the placement rules below. Your turn ends immediately.

2. Jump (Capture)

Jump one of your existing pieces over an adjacent enemy piece to capture it. Jumps can be:

• Orthogonal (up, down, left, right) -- 2 squares in one direction
• Diagonal -- 2 squares diagonally

The piece you jump over is marked for capture, and your piece lands on the empty intersection beyond it.

Before:          After jump:
. . . . .        . . . . .
. W . . .        . . . . .
. . B . .   -->  . . x . .    (x = captured, pending removal)
. . . . .        . . . W .
. . . . .        . . . . .

Chain Jumps

After completing a jump, if your piece can make another legal jump from its new position, you may continue jumping with the same piece. You can chain as many jumps as are available.

Confirming a Jump

After one or more jumps, you must confirm to end your turn. All captured pieces are removed from the board and added to your score. Until you confirm:

• You cannot place a new piece.
• You can only continue jumping with the same piece.
• You can undo individual jump steps to try a different path.

Placement Rules

Placing a piece is subject to two constraints:

Cluster Rule

A group of connected same-color pieces (orthogonally adjacent) cannot exceed 10 stones. If placing your piece would create or expand a connected cluster beyond 10, the placement is illegal.

Example: 10 white stones in a row is OK.
         Placing an 11th adjacent stone is BLOCKED.

W W W W W W W W W W .    <-- 10 stones: legal
W W W W W W W W W W X    <-- 11th stone here: ILLEGAL

Border Rule

You cannot place a piece on the edge of the board (row 0, row 18, column 0, or column 18) unless an enemy piece could reach that position through a jump sequence. This prevents safe "parking" of pieces on the borders where they cannot be captured.

Edge of board:

. . .
. W .      White at (1,1), black at (1,0) -- border placement at (1,0) is
B . .      ALLOWED because black is there and could be jumped into

. . .
. W .      No enemy nearby -- border placement at (0,0) is
. . .      BLOCKED

Winning

The first player to capture 10 enemy pieces wins the game. Once a player's score reaches 10, the game is over and no further moves are allowed.

Summary

Rule	Description
Board	19x19 empty grid
First move	White
Place	Put a piece on an empty intersection (subject to cluster + border rules)
Jump	Leap 2 squares over an enemy piece (orthogonal or diagonal) to capture
Chain jumps	Continue jumping with the same piece if possible
Confirm	End your jump sequence, remove captured pieces, score points
Cluster limit	Max 10 connected same-color pieces
Border limit	Edge placements must be reachable by an enemy jump
Win condition	First to capture 10 enemy pieces

Error Codes

When a move is illegal, the game engine returns one of these codes:

Code	Meaning
GAME_OVER	The game has already ended
OUT_OF_BOUNDS	Position is outside the 19x19 board
OCCUPIED	That intersection already has a piece
PENDING_JUMP	You must finish the current jump sequence first
INVALID_CLUSTER	Placement would violate the cluster rule
INVALID_BORDER	Border placement is not allowed here
NO_PIECE	No piece at the jump origin
NOT_YOUR_PIECE	That piece belongs to your opponent
INVALID_JUMP	The jump is not legal from this position
NO_PENDING_JUMP	No jump sequence in progress to confirm or undo